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Looking at the Earth from above
Jun 15th 2019 / San Francisco and Didcot
In May 1999 a group of researchers from the Technical University of Berlin launched an unusual satellite. At a time when most of the machinery in orbit weighed thousands of kilograms, TUBSAT was a petite 45kg. A box that measured 32cm on each side, it carried three video cameras, the idea being to test whether such a titchy spacecraft could capture useful imagery of Earth. The researchers cited low mass, and the resultant low costs, as the benefits of such comparatively tiny satellites. They promised to open up "new market areas" for Earth observation.
It took around 15 years for them to be proved right. A few such "smallsats", sometimes called nanosats or CubeSats, were launched every year in the decade up until 2014, when numbers spiked. Planet Labs, a Californian company founded by ex-Nasa engineers, launched 33 smallsats that year, each weighing just a few kilos. Planet's satellites are spiritual successors of TUBSAT, designed to gather imagery of the Earth's surface. The firm sells its customers images from around 150 active satellites it has in orbit.
Planet Labs is an industry leader. The cost of making and launching satellites has tumbled, enabling an array of new space-based businesses to emerge. In the past year smallsats have been launched that can use radar to peer through clouds or darkness. Others watch for illegal shipping activities and yet more are built to service or move around other satellites in orbit. Perhaps the most outlandish venture is a rescue satellite, designed to pull other satellites down to safety if something goes wrong, to avoid catastrophic collisions with neighbours.
Much of the recent attention has focused on the internet-connection constellations in low Earth orbit proposed by SpaceX and OneWeb. These have long been planned, and the billions of dollars required to install them are feeding the entire market.
Many of the capabilities of the new smallsats already existed, but mostly as government projects or as secretive intelligence operations. America has long sought to inhibit the commercial development of radar satellites, so powerful are their surveillance properties. military radar satellites, which bounce radio waves off the surface of the Earth in order to build up a detailed picture of it, were said to be capable of detecting enemy submarines by measuring the tiny disturbances that their wakes left in the curvature of the surface of the ocean.
Payam Banazadeh, the boss of Capella Space, a startup based in San Francisco and founded in 2016, says his firm will use smallsats to work similar magic. Capella's satellites will use radio waves, rather than light, to create images of the surface of the Earth. Mr Banazadeh says that his smallsats will be able to measure the volume of oil-storage tanks, for example, which are often open-topped to avoid fire risks, simply by pinging a radar beam into them. The first operational satellite is intended to launch this year, one of a planned constellation of 36. A competitor, Finnish company ICEYE, already has satellites in orbit gathering data.
Capella relies on a host of new space businesses as suppliers. Blue Canyon Technologies, founded in 2008, will provide small thrusters that allow the satellites to be pointed at specific spots on Earth. A company called Phase Four, founded in 2015, will provide tiny ion drives that will allow Capella's satellites to adjust their altitude as needed. This will let the firm capture a wider variety of imagery.
Another new firm, Hawkeye360, takes a different approach. Instead of pinging the surface of the Earth with radio waves, it listens for any that are being emitted by activity down below. This kind of orbital signal sniffing also used to be the domain of governments. But smallsats have advanced to the point where Hawkeye can deploy clusters of three radio-frequency sensing satellites to pick up weak signals from the ground. The company says its primary service will be maritime surveillance, looking for anomalous radio signals such as a fishing vessel turning off its automated identification tracker near a marine protected zone. The stated purpose is to stop illegal fishing and keep ports secure, but it is easy to see how the smallsats could be used to curb oceanic migration too. Hawkeye's first cluster of Satellites has been in orbit since December 2018.
The data deluge
All of these new forms of imaging generate huge volumes of data - terabytes a day, enough that getting it down to the ground for processing becomes its own problem. Some companies want to reduce the amount of data they send back by processing some of it up in space. Barry Matsumori, a space-industry veteran, is boss of Bridgesat, a company that has developed a tiny, powerful laser, which can be embedded in spacecraft and which can beam data down to ground stations at extremely high bandwidths. ICEYE is one of its first customers. Bridgesat's first ground station, in California, is already in operation, and more in Italy and Sweden are on their way. The plan is to have ten around the world.
The firm has competition from Amazon, which just announced its own backbone service for data out of orbit and into its data centres, called AWS Ground Station. Capella is an early customer of the service, which uses radio waves rather than lasers to get data down from orbit. As with Amazon's cloud-computing business, the idea with Ground Station is to invest in plenty of expensive infrastructure and then charge startups only for what they use, making it easier and more affordable to run a business up in space.
Managing all those extra satellites gets tricky when the companies launching them have to get their orbits perfect the first time. Currently, companies get only one shot. D-Orbit, an Italian company, has built a "carrier" satellite that is designed to boost already-launched smallsats to their correct configuration.
Perhaps the most futuristic new problem for the space business is the risk of debris. The concern is that, with so many new satellites in orbit operated by so many different companies, the chance of losing control of one goes up. A collision could be disastrous, producing a wave of debris with a high chance of wiping out other satellites, potentially crippling the whole commercial low-Earth orbit ecosystem at a stroke. Astroscale, a Japanese company, is tackling this problem by building a prototype craft capable of being launched at short notice in order to grab any malfunctioning satellite and pull it down into the atmosphere where it will burn up before it can collide with anything. The "rescue" craft will use computer vision to lock onto the out-of-control satellite and match velocity with it, then latch onto it magnetically. The company, which has raised $132m in the past few years, is planning a demonstration of its technology next year.
Earth's orbits suddenly look busier than ever before. Companies are going into space because it offers a different vantage point, allowing them to gather valuable new, previously-unaffordable information. TUBSAT's "new market areas" are at last open for business.
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